;;; cal-iso.el --- calendar functions for the ISO calendar
-;; Copyright (C) 1995, 1997 Free Software Foundation, Inc.
+;; Copyright (C) 1995, 1997, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
+;; 2008 Free Software Foundation, Inc.
;; Author: Edward M. Reingold <reingold@cs.uiuc.edu>
+;; Maintainer: Glenn Morris <rgm@gnu.org>
;; Keywords: calendar
;; Human-Keywords: ISO calendar, calendar, diary
;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 2, or (at your option)
+;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING. If not, write to the
-;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
;;; Commentary:
-;; This collection of functions implements the features of calendar.el and
-;; diary.el that deal with the ISO calendar.
-
-;; Technical details of all the calendrical calculations can be found in
-;; ``Calendrical Calculations'' by Nachum Dershowitz and Edward M. Reingold,
-;; Cambridge University Press (1997).
-
-;; Comments, corrections, and improvements should be sent to
-;; Edward M. Reingold Department of Computer Science
-;; (217) 333-6733 University of Illinois at Urbana-Champaign
-;; reingold@cs.uiuc.edu 1304 West Springfield Avenue
-;; Urbana, Illinois 61801
+;; See calendar.el.
;;; Code:
(require 'calendar)
-(defun calendar-absolute-from-iso (date)
+(defun calendar-iso-to-absolute (date)
"The number of days elapsed between the Gregorian date 12/31/1 BC and DATE.
The `ISO year' corresponds approximately to the Gregorian year, but
weeks start on Monday and end on Sunday. The first week of the ISO year is
commercial DATE has the form (week day year) in which week is in the range
1..52 and day is in the range 0..6 (1 = Monday, 2 = Tuesday, ..., 0 =
Sunday). The Gregorian date Sunday, December 31, 1 BC is imaginary."
- (let* ((week (extract-calendar-month date))
- (day (extract-calendar-day date))
- (year (extract-calendar-year date)))
+ (let ((day (extract-calendar-day date)))
(+ (calendar-dayname-on-or-before
- 1 (+ 3 (calendar-absolute-from-gregorian (list 1 1 year))))
- (* 7 (1- week))
- (if (= day 0) 6 (1- day)))))
+ 1 (+ 3 (calendar-absolute-from-gregorian
+ (list 1 1 (extract-calendar-year date)))))
+ ;; ISO date is (week day year); normally (month day year).
+ (* 7 (1- (extract-calendar-month date)))
+ (if (zerop day) 6 (1- day)))))
+
+(define-obsolete-function-alias 'calendar-absolute-from-iso
+ 'calendar-iso-to-absolute "23.1")
(defun calendar-iso-from-absolute (date)
"Compute the `ISO commercial date' corresponding to the absolute DATE.
(calendar-gregorian-from-absolute (- date 3))))
(year (+ approx
(calendar-sum y approx
- (>= date (calendar-absolute-from-iso (list 1 1 (1+ y))))
- 1))))
+ (>= date (calendar-iso-to-absolute
+ (list 1 1 (1+ y))))
+ 1))))
(list
- (1+ (/ (- date (calendar-absolute-from-iso (list 1 1 year))) 7))
+ (1+ (/ (- date (calendar-iso-to-absolute (list 1 1 year))) 7))
(% date 7)
year)))
+;;;###cal-autoload
(defun calendar-iso-date-string (&optional date)
- "String of ISO date of Gregorian DATE.
-Defaults to today's date if DATE is not given."
+ "String of ISO date of Gregorian DATE, default today."
(let* ((d (calendar-absolute-from-gregorian
(or date (calendar-current-date))))
(day (% d 7))
(extract-calendar-month iso-date)
(extract-calendar-year iso-date))))
-(defun calendar-print-iso-date ()
+;;;###cal-autoload
+(defun calendar-iso-print-date ()
"Show equivalent ISO date for the date under the cursor."
(interactive)
(message "ISO date: %s"
(calendar-iso-date-string (calendar-cursor-to-date t))))
-(defun calendar-goto-iso-date (date &optional noecho)
- "Move cursor to ISO DATE; echo ISO date unless NOECHO is t."
- (interactive
- (let* ((today (calendar-current-date))
- (year (calendar-read
- "ISO calendar year (>0): "
- '(lambda (x) (> x 0))
- (int-to-string (extract-calendar-year today))))
- (no-weeks (extract-calendar-month
- (calendar-iso-from-absolute
- (1-
- (calendar-dayname-on-or-before
- 1 (calendar-absolute-from-gregorian
- (list 1 4 (1+ year))))))))
- (week (calendar-read
- (format "ISO calendar week (1-%d): " no-weeks)
- '(lambda (x) (and (> x 0) (<= x no-weeks)))))
- (day (calendar-read
- "ISO day (1-7): "
- '(lambda (x) (and (<= 1 x) (<= x 7))))))
- (list (list week day year))))
+(define-obsolete-function-alias 'calendar-print-iso-date
+ 'calendar-iso-print-date "23.1")
+
+(defun calendar-iso-read-date (&optional dayflag)
+ "Interactively read the arguments for an ISO date command.
+Reads a year and week, and if DAYFLAG is non-nil a day (otherwise
+taken to be 1)."
+ (let* ((year (calendar-read
+ "ISO calendar year (>0): "
+ (lambda (x) (> x 0))
+ (int-to-string (extract-calendar-year
+ (calendar-current-date)))))
+ (no-weeks (extract-calendar-month
+ (calendar-iso-from-absolute
+ (1-
+ (calendar-dayname-on-or-before
+ 1 (calendar-absolute-from-gregorian
+ (list 1 4 (1+ year))))))))
+ (week (calendar-read
+ (format "ISO calendar week (1-%d): " no-weeks)
+ (lambda (x) (and (> x 0) (<= x no-weeks)))))
+ (day (if dayflag (calendar-read
+ "ISO day (1-7): "
+ (lambda (x) (and (<= 1 x) (<= x 7))))
+ 1)))
+ (list (list week day year))))
+
+(define-obsolete-function-alias 'calendar-iso-read-args
+ 'calendar-iso-read-date "23.1")
+
+;;;###cal-autoload
+(defun calendar-iso-goto-date (date &optional noecho)
+ "Move cursor to ISO DATE; echo ISO date unless NOECHO is non-nil."
+ (interactive (calendar-iso-read-date t))
+ (calendar-goto-date (calendar-gregorian-from-absolute
+ (calendar-iso-to-absolute date)))
+ (or noecho (calendar-iso-print-date)))
+
+(define-obsolete-function-alias 'calendar-goto-iso-date
+ 'calendar-iso-goto-date "23.1")
+
+;;;###cal-autoload
+(defun calendar-iso-goto-week (date &optional noecho)
+ "Move cursor to ISO DATE; echo ISO date unless NOECHO is non-nil.
+Interactively, goes to the first day of the specified week."
+ (interactive (calendar-iso-read-date))
(calendar-goto-date (calendar-gregorian-from-absolute
- (calendar-absolute-from-iso date)))
- (or noecho (calendar-print-iso-date)))
+ (calendar-iso-to-absolute date)))
+ (or noecho (calendar-iso-print-date)))
+
+(define-obsolete-function-alias 'calendar-goto-iso-week
+ 'calendar-iso-goto-week "23.1")
+
+(defvar date)
+;; To be called from diary-list-sexp-entries, where DATE is bound.
+;;;###diary-autoload
(defun diary-iso-date ()
"ISO calendar equivalent of date diary entry."
(format "ISO date: %s" (calendar-iso-date-string date)))
(provide 'cal-iso)
+;; arch-tag: 3c0154cc-d30f-4981-9f60-42bdf7a468f6
;;; cal-iso.el ends here
HCoop / bpt / emacs.git / blobdiff